1. Field of the Invention
The present invention relates to a balloon catheter in which a balloon can indwell a blood vessel after being separated from a catheter body in response to a high-frequency electrical power. More particularly, the present invention is concerned with a method of and an apparatus for separating a balloon of a balloon catheter from the catheter body.
2. Description of the Related Art
A typical known balloon catheter has, as disclosed in Japanese Pat. Examined Publication No. 60-30225, a catheter body which is provided at its one end with a needle or connector, and a balloon which is connected to the catheter body through a connecting member. The connecting member through which the catheter body and the balloon are connected to each other is provided with a dipole electrode composed of a pair of electrode members. These electrode members are respectively connected through lead lines to lead terminals which are provided on the end of the catheter body adjacent to the needle.
The balloon on the end of the balloon catheter is made from a rubbery material and is adapted to be charged with a curable or settable liquid.
In use, the balloon catheter is guided through a blood vessel to reach an affected portion of the blood vessel and then the settable liquid is supplied into the balloon, whereby a treatment called embolization is conducted. This treatment is used in, for example, remedy of various cerebrovascular diseases such as cerebral aneurysm, intracanial srteriovenous malformation, carotid cavernous angioma and so forth. In general, sideration ages of these diseases are comparatively young. These diseases are generally completely curable when a suitable treatment is taken. In addition, in case of such diseases, the affected part can hardly be accessed by surgical means. These are the reasons why embolization by means of a balloon catheter is widely used in the remedy of these diseases. Usually, the balloon catheter is guided from a femoral artery and to the affected part through an observation of an X-ray image. Then, a settable liquid mainly composed of fibronogen is injected into the balloon and allows the liquid to set thereby embolizing the affected part. After the setting of the settable liquid, a high-frequency electrical power is supplied to the dipole electrode so as to melt and cut the connecting member. Thus, the connecting member is made of a meltable material and the balloon after the separation indwells the blood vessel.
This known balloon catheter requires a complicated catheter operation in order to guide the catheter to the affected part of the blood vessel which requires remedy. If any short-circuiting is taking place between the lead lines, the separation between the catheter body and the balloon after the setting of the settable liquid cannot be effected even by the supply of the electrical power to the electrode members on the catheter, with the result that the catheter body itself is dangerously left in the blood vessel together with the balloon.